Micromanipulator



Oct. 17, 1961 T. N. Ross 3,004,439

MICROMANIPULATOR Filed Nov. 23. 1959 IN VEN TOR. 7710/4/15 /V. 5055 United States Patent 3,004,439 MICROMANIPULATOR Thomas N.-Ross, 715 th Ave. N.,' Seattle, Wash.

. Filed Nov. 23, 1959, Set. No. 854,867

.6 Claims. (Cl. 74-18.1)

This invention concerns a motion transmitting device, such as a micromanipulator, by means of which a lever moved by hand or in response to some other force causes an associated needle to perform identical movement, but of much smaller amplitude.

Such devices haveoften been of rather appreciable complexity of construction, and consequent possibility of malfunctioning. They have also been correspondingly expensive. Itis an object of this invention to simplify the construction of such a device, and so to lessen its cost, while at the same time improving its ruggedness and reliability. I

Most micromanipulators have inherently a fixed ratio between the amplitudes of movement of the lever and needle, respectively. Another object of this invention, in one embodiment, is to permit the selection of difierent ratios between these amplitudes.

The micromanipulator of this invention is shown in the drawings in two representative forms, which will be described herein generically and specifically, and the novel principles whereof will be defined in the accompanying claims.

FIGURE 1 is an isometric view of a simple embodiment, although one lacking the facility of varying the ratio of amplitudes.

FIGURE 2. is a longitudinal elevational view, and FIG- URE 3 an elevational view from the needle end, of the same form.

FIGURE 4 is a view similar to FIGURE 2 of a modified form, having the capability of varying theratio of amplitudes.

The reduction of motion of the needle as compared to the lever or handle, in this micromanipulator, derives from gradation of strain in a deformable elastic member, as between its region of fixed support and its region of greatest amplitude of movement. The handle will be connected to the deformable member at the region of greatest amplitude, and the needle will be connected to the same member intermediate that region and the region of fixed support, where amplitude is zero. By choosing the region for connection of the needle the ratio of its amplitude to the amplitude of the handle may be anything desired, approaching zero at one end of the range, and one to one at the other end. These principles are illustrated in the micromanipulator that will now be described in some detail.

The micromanipulator is supported by a rigid support, immovable during use, such as the base 4 adapted to rest upon a table and the upstanding flange 40 at one end. The flange 40 has a substantially circular aperture 41, the size of which may vary depending upon the degree of sensitivity or the amplitude of movement desired. A deformable elastic support is engaged within the aperture 41, or about its periphery. For example, a thick disk 3 of rubber-like material is of a size to fit within the aperture. 41, and is held therein by retaining rings 42. The disk is variably subject to flexing at diiferent radii. The disks amplitude of movement about its periphery is substantially zero, and at its center is a maximum.

A lever or handle 2 is aflixed to the center of the disk 3, which is the region most distant from its region of zero amplitude, as by the opposite nuts 21 threaded on the end of the lever which penetrates the disk. The lever 2 is directed away from the disk, along its axis. Its outer end is arranged at 22 for engagement by the manipulators fingers.

3,004,439 Patented Oct. 17, 1961 v The needle 1 alsois supported from and extends along the axis of the disk 3, oppositely to the lever 2. Its support at the disk is about a circle intermediate the diskscenter and its periphery, and the nearer is this circle to the center the smaller is the ratio of amplitude of movement of the lever to that of movement of the needle, and conversely, the farther is this circle from the center the larger is the same ratio. This is due to the characteristic of the disk mentioned above, that it is variably subject to' flexing at different radii. As shown, the inner end of the needle is supported by a tripod 1 1, the ends of the legs whereof penetrate the disk 3 about the desired circle.

In use, the free end of the lever 2 will be movable, because of the high degree of flexibility of the disk 3 at its center point, in a large circle represented in FIG- URE 1 at 20. The free end of needle 1, because of the lesser degree of displacement of the disk about the circle of needle support as compared to the given displacement at its center, will move identically to the lever, in a circle 10, but the needles movement will be of lesser amplitude. The nearer thedisks periphery is the needles circle of support, the smaller is the needles amplitude of movement for movement of the lever by a given amplitude.

Not only will corresponding but reduced movement of the needles end in a circle result from circular movement of the levers end, but axial displacement of the lever will produce corresponding but less movement of the needle, as FIGURE 2 illustrates, and for like reasons. If desired, the disk 3 can be mounted to rotate within the aperture 41, which will 'not aifect the relative movements of lever and needle. y

The form shown in FIGURE 4 employs a'flexi'ble bellows 31, open at one end and closed at its other end, as the flexible support. Its open end is secured to the rigid support flange 40 about the periphery of its aperture 41. The lever 2 is secured at the center point of its closed end. A tripod support could be employed for the needle 1, but a somewhat conical or belled support 12 is shown, the periphery of which is received within a circular groove of the bellows 31. The relative amplitudes of the lever and needle now depend upon the axial distance of the circle of engagement of the belled support 12 relative to the fixedly secured open end of the bellows and the closed end thereof, respectively. The nearer the periphery of the bell 12 is to the secured end of the bellows, the lower is the ratio of amplitude of the needles end to the amplitude of the levers end. Here, too axial movement of the lever is reproduced on a smaller scale by the needle, as well as circular movement.

By shifting the bell 12 axially of the bellows 31 the relative amplitudes of lever and needle can be altered.

Instead of securing the disk 3 about its periphery it might be secured at its center, in which case the lever 2 would be secured about its periphery, which then would be its region of greatest amplitude; the needle 1 would still be secured intermediate the regions of greatest and of zero amplitude. A similar inversion of the bellows form might be effected. Also, a multiplicity of elastic elements might be employed.

Such a device has a number of advantages over known micromanipulators. It is, for one, made simply of inexpensive materials. It is very easy to use, all motions being instinctive, as if the manipulation were'being performed directly with a hand-held probe. Its speed of operation is high, for all control is centered in the single lever, and there is no need to shift the hand from one control to another. It does not develop excessive forces at the working point, for the force as well as the amplitude is graduated, and there is no danger of destroying delicate structures by overload. The device is also inherently free of backlash.

I claim as my invention:

{1. A motion-transmitting device comprising a deformable elastic element, supporting means fixedly engaged with said element in a given region, the elements deformation under strain in such region being 'zero, but its deformation in a distant region being a maximum, a handle secured to said element "in the region or maximum deformation, and a needle secured to said element in a region intermediate the regions of maximum and zero deformation, and movable by said clement correspondingly to movement of the element by said handle, but 'a't reduc'ed amplitude. V

2. A miei-omanipulator comprising an apertured "rigid support, a deformable elastic support fixedly secured at one extremity about said aperture, alever secured to said elastic support at its ,point most distant from its fixed extremity and rndst'fiexible in relation thereto, and a needle supported from said elastic support abouta circle intermediate said most flexible point and its fixed extremity; V

3. A micron anipu'l-ator as in claim 2, wherein the needle is removably 'engaged with the flexible support, for engagement about selected circles -a't varying relative distances between the fixed extremity and the most flexible point of the flexible support;

4. A micrornanipulator comprising an apertured rigid support, a deformable ela's'tic support secured about its periphery in said rigid support, a lever secured to said deformable support substantially at its central point, whereby to flex the deformable support along a line transverse to the plane of the aperture and tiltably about a point in such line, and extending from said deformable support generally along such line, :and a needle extending from said deformable support generally in the same line but oppositely from said lever, and secured to said deformable support about a circle located intermediate its center and its periphery.

5. A micromanipulator comprising a rigid support having a substantially circular aperture, an elastically deformable diaphragm secured about its periphery in such aperture, and thereby held immovably with respect to said support about such periphery but having increasing flexibility towards its center, a lever extending from one face of said diaphragm and secured to the mostflexible central point of the latter, and a needle extending from the opposite face of said diaphragm, generally in line with the lever, and secured to the diaphragm about a circle located intermediate its center and it's 'periphery.

*6. A micromanipulator comprising a rigid support having asubstantially circular aperture, a flexible bellows closed at one end and peripheral-1y secured at its opposite end about such aperture, a lever extending from its closed end, in substantial axialalignment with the bellows, a needle having mounting means at one end for engaging the bellows about a periphery intermediate the bellows ends, and extending thence generally along the axis of the bellows, but-oppositely to said lever.

References Cited in the file of this patent UNITED STATES PATENTS 

